It is exceedingly well known to employ an elongated plenum having side walls, a bottom wall and a top deck surface for use in conveying objects such as cans. Characteristically, the top deck surface is provided with an array of slit openings for the directional discharge of air from the interior of the elongated plenum. Objects placed upon the top deck surface are caused to move over said surface in response to pressurization of the plenum and resulting discharge of air through the array of slit openings.
Pressurization of various plenum assemblies has been carried out through the use of scroll housings placed about wheel fans. These housings are generally placed at an extremity of the plenum or air conveyor segment causing air to be drawn from the ambient surroundings and directionally injected within the elongated plenum structure from the scroll housing itself or from a transition duct.
It has recently been suggested in U.S. Pat. No. 4,392,760, which was issued on July 12, 1983, the disclosure of which is incorporated by reference herein, that the scroll housing be eliminated and that an open wheel fan be mounted directly within the plenum of a surface flow air conveyor. It was recognized by this patented reference that although scroll housings were conventionally taught to be employed to obtain maximum outlet pressure, by placing an open wheel fan within the plenum itself, increased performance could be achieved.
Although the teachings of U.S. Pat. No. 4,392,760 represented an advance in the art, implementation o this invention was not without its shortcomings. More specifically, the open wheel fan assemblies were taught to be employed within a side wall of the plenum or in a pod structure beneath the plenum whereby a horizontally aligned shaft was employed connecting an electric motor to the fan wheel. Such a configuration resulted in a motor assembly and filter housing protruding on one or both sides of the plenum structure which would limit the user in placement of the plenum proximate a solid wall or a parallel air conveyor assembly. One could not walk parallel to the air conveyor without tripping or maximize assembly nesting through the use of parallel lines. In addition, it was found that in placing the wheel fan assembly on a horizontally extending shaft through the side wall of the plenum as taught in U.S. Pat. No. 4,392,760, efficiency, as measured by pressure output for a specific motor was not optimized.
It is thus an object of the present invention to provide an air conveyor while eliminating the shortcomings of the prior art.
It is thus a further object of the present invention to provide an air conveyor assembly wherein a high performance wheel fan member is placed directly within the air conveyor plenum while eliminating the shortcomings inherent in the design disclosed and claimed in U.S. Pat. No. 4,392,760.
These and further objects will be more readily apparent when considering the following invention and appended drawings wherein;
the sole appended figure represents a side elevational view of a structure representing the present invention.